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whitepoint

XYZ color values of standard illuminants

Syntax

xyz = whitepoint(illuminant)
xyz = whitepoint

Description

xyz = whitepoint(illuminant) returns xyz, a three-element row vector of XYZ values scaled so that Y = 1. illuminant specifies the white reference illuminant. The following table lists all the possible values.

ValueWhite Point
'a'

CIE standard illuminant A, [1.0985, 1.0000, 0.3558]. Simulates typical, domestic, tungsten-filament lighting with correlated color temperature of 2856 K. 

'c'CIE standard illuminant C, [0.9807, 1.0000, 1.1822]. Simulates average or north sky daylight with correlated color temperature of 6774 K. Deprecated by CIE.
'e'Equal-energy radiator. Useful as a theoretical reference. [1.000, 1.000, 1.000].
'd50'CIE standard illuminant D50, [0.9642, 1.0000, 0.8251]. Simulates warm daylight at sunrise or sunset with correlated color temperature of 5003 K. Also known as horizon light.

'd55'

CIE standard illuminant D55, [0.9568, 1.0000, 0.9214]. Simulates mid-morning or mid-afternoon daylight with correlated color temperature of 5500 K.  

'd65'CIE standard illuminant D65, [0.9504, 1.0000, 1.0888]. Simulates noon daylight with correlated color temperature of 6504 K. 
'icc'Profile Connection Space (PCS) illuminant used in ICC profiles. Approximation of [0.962, 1.000, 0.8249] using fixed-point, signed, 32-bit numbers with 16 fractional bits.  Actual value: [31595,32768, 27030]/32768.

xyz = whitepoint is the same as xyz = whitepoint('icc').

Class Support

illuminant is a character array. xyz is of class double.

Examples

Return the XYZ color space representation of the default white reference illuminant 'icc'.

wp_icc = whitepoint

wp_icc =

    0.9642    1.0000    0.8249

Introduced before R2006a

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